Caulk Gun with a Set of Shortened Rods

ABSTRACT

This invention is a gun shaped device used in the application of caulk, paste and or other semi solid high viscosity fluids. The device contains a barrel portion for the tube to be inserted into, and a plunger portion with a flat round metal piece with a fitting that attaches to a set of shortened rods. The set of shortened rods acts as a plunger and goes through a guide toward the back of the handle. The barrel can be shortened for use of smaller tubes of caulk.

BACKGROUND Field of Invention

The present invention is related to the use and delivery of a semisolid paste via a gun like device which can squeeze the paste out of the tube at a rate consistent with the desires of the user. More particularly, the present invention is related to extendable plungers and the triggers for them.

Description of the Related Art

Prior art designs for caulk guns are a well-known feature of the construction marketplace. They can be used to seal cracks and crevices, to permanently fix a piece of glass into its frame, or to keep a set of shelves from moving. They generally allow for the placement of a rigid tube or a softer tubular bag of a high viscosity liquid or paste in the barrel of the device and eject the paste through a nozzle at the front end.

A typical hand operated caulk gun is exemplified in FIG. 1 with a rigid piston rod (6) and a flat round plunger slidably placed in a channel extending from a hole in the back of the handle to the back of the container of the said tube or tubular bag of paste. The tube housing (5) is generally sized to fit either a 9 oz or a 29 oz cylindrical tube of paste. The operation of the typical commercially available caulk gun generally involves the advancement of a rigid metal rod with a flat round plunger at the end that can slide into the barrel, reducing the volume of caulk in said tube of paste. This caulk gun starts with a full tube of paste or viscous liquid and the piston rod fully extended such that the clearance required for the caulk gun is more than double the length of said tube of viscous liquid plus the length of the nozzle, and the handle/trigger housing. It has a tube housing (5) in which said tube is placed into with the nozzle pointed forward to the far end of the barrel. The ridged piston rod generally has a hook on the end to allow the user to either turn the angle of the piston rod to release the pressure on said tube of caulk or to quickly pull the plunger out when the tube is empty.

The trigger handle (7) is used to engage the drive grip (8) and move the piston (6) forward to deliver the caulk in a bead of a consistent size and width. When the piston (6) is fully retracted the length of the caulk gun is nearly 2× the length of the tube housing (5) and the trigger housing (9). The drive grip and the trigger handle are resisted by a spring that is in a rest position when the trigger handle is released.

SUMMARY OF THE INVENTION

The current invention is a modified caulking gun for use in areas with a small amount of clearance for the space in front of the joint to be sealed. The caulk gun has the features, a shortened tube housing to fit a cylindrical tube of caulk that is smaller than the standard 9 oz tube, a segmented plunger, a handle, a trigger, a frictional tab with the means to release the pressure on the plunger, and a cut out area in the body for the insertion of the caulking tube.

The segmented plunger will comprise a flat round metal piece that is attached on the end of a set of short rods that can be quickly combined or separated to form a rod of variable length. Disposed at the back of the handle is the thumb lock and release mechanism that prevents shortened rods from being pushed all the way into the caulk gun. The thumb lock will work in conjunction with a groove positioned near one end of a shortened rod.

The benefits of this invention include but are not limited to the unencumbered use of the caulking gun in restricted space environments. A smaller caulking gun with greater clearance at the rear of the caulk gun allows the caulk to be laid at more precise angles than a larger caulking gun, and the more versatile plunger allows for a more convenient use of the space directly behind the gun handle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a prior art caulk gun with a rigid smooth piston rod.

FIG. 2 is a cut out view of the caulk gun, the trigger handle fully forward.

FIG. 3 is a top view of the caulk gun, the trigger handle fully forward.

FIG. 4 is a perspective view of the caulk gun.

FIG. 5 is a back view of the caulk gun.

FIG. 6 is a cut out view of the shortened rod.

FIG. 7 is a perspective view of the shortened rod.

DETAILED DESCRIPTION

Referring now to the invention shown in FIG. 2 a cutout view of a caulking gun shows a view of said caulking gun with a tube housing (11) to fit a shorter tube of caulk (about 4-7 oz is optimal), and a segmented plunger assembly with a set of shortened rods and a round disk (not shown) that attaches to the male portion of the shortened rods (18). This view shows the path of the shortened rod (13) that passes through a spring (16), two holes in the handle, and a frictional tab (15). The caulk gun is shown with a handle (14) and a trigger (12) attached at one point, and a frictional tab (15) attached to the trigger at a different point. The rear of the shortened tube housing (11) attaches to the front of the handle (14). In this embodiment the shortened tube housing (11) is attached with a metal-to-metal connection to the front side of the handle with connections that can range from welding a sharp edge to the shortened tube housing (11) or the use of a folded piece of metal, or the use of screws, bolts, or rivets.

Further referring now to the invention shown in FIG. 2-5, a shortened rod (13) or a set of the shortened rods (13) passes through a hole in the back of the handle (21), the frictional tab (15), a spring (16) and the hole in the back of the shortened tube housing (22). At the front of the first shortened rod is a pan shaped disk (not shown, but similar to feature 5 of FIG. 1) that can screw onto a threaded male connection (18). Once attached to the pan shaped disk, a slow steady insertion of the shortened rod (13) by the action of the trigger (12) and the frictional tab (15) is stopped by the action of a thumb lock release mechanism (17) near the hole in the back of the handle (21) on the groove (19) on the back end of the shortened rod (13). As seen in FIG. 2-4 the shortened rod (13) is longer than the distance from the hole in the back of the handle (21) to the hole in the back of the shortened tube housing (22).

Referring now to the invention shown in FIG. 3 with a top view of the caulk gun. This view shows the thumb lock/release mechanism (17) is attached to the back side of the shortened tube housing (11). The thumb lock/release mechanism (17) is a thin strip that follows along the edge of the handle with the axis of the caulking gun, wrapping around the back of the handle (14) ending with a mechanical button (23). The thumb lock/release mechanism is under tension and when aligned will engage with the groove (19) to stop the shortened rod (13) from moving until pressure is applied to the mechanical button (23) on the front side of the handle. With the shortened rod (13) or segmented plunger assembly held by the thumb lock/release mechanism another male connection of another of the shortened rods can be added to the female connection (20) of the shortened rod (13). In one embodiment, the combination of the thumb lock release mechanism and the thumb lock groove will lock the shortened rod into place allowing for the male connection (18) for a second shortened rod to be screwed into the female connection (20) in the back of the shortened rod (13). The female connection (20) is also threaded such that it may join with the male connection.

Further referring now to the invention shown in FIG. 2-5 when the trigger (12) is pulled, the frictional tab (15) will engage. The frictional tab (15) will turn slightly upon a trigger pull with the top and bottom collapsing onto the segmented plunger assembly, acting like a pincher. The frictional tab (15) has a levered connection (24) with the trigger (12) which on a trigger pull will move the shortened rod (13) forward with significant leverage. The trigger (12) works on a different axis of rotation versus the levered connection (24) with the trigger. These elements working together smooth the forward motion of the plunger, giving a smooth and steady supply of caulk or adhesive. The tube housing (11) holds the outside of the shortened caulking tube in place.

Further referring now to the invention shown in FIG. 4-5. FIG. 4 a perspective view of the caulk gun, and FIG. 5 a back view of the caulk gun, best show the action of the mechanical button (23) when pressed. When the mechanical button (23) is pressed the thumb lock/release mechanism (17) acts against the spring action of the metal strip releasing the shortened rod (13).

Further referring now to the invention shown in FIG. 2, the plunger will comprise a flat round metal piece that is attached to the male end of the shortened rod (13). When the shortened rod is inserted into the handle it is surrounded by elements in the following order, the hole in the back of the tube housing (22), the spring (15), the frictional tab (15), and the hole at the back of the handle (21).

Referring now to the invention shown in FIG. 6-7. In this embodiment, the shortened rod (35) comprises, the male connection (31), the female connection (32), the thumb lock groove (33), and a main length section (34). The shortened rod can be used alone but works better in groups of two or more as it is intended to be ½ or less the length of the caulking gun from the front of the tube housing to the back of the trigger handle, but longer than the distance from where the thumb lock groove mechanism (17) should meet with the shortened rod and the front of the handle. Said group of two or more shortened rods can be a set of rods with each rod being substantial in size but not necessarily the same size as the shortened rod (31) contiguous with the flat round disk of the plunger. The male connection (31) is generally threaded, but a push lock system can be imagined, and can connect to either the plunger tip which is shaped like a pie pan with a female nut attached to the middle, or the female connection of another shortened rod. Both the male connection (31) and the female connection (32) are threaded and given groove patterns such that they will connect and reversibly bind to each other.

Referring now to the invention shown in FIG. 6-7 the main length (34) of the shortened rod (35), from the male connection (31) to the thumb lock groove (33) is longer than the distance from the back of the tube housing to the back of the trigger handle when on the middle axis of the tube when placed in the tube housing. The thumb lock groove (33) is wide enough for the thumb lock mechanism to easily slide into it as the shortened rod is worked into an adjacent position. It is imagined that the thumb lock groove would have serrations or imperfections in the circular structure wherein when another shortened rod is pushed up to it and rotated the shortened rod would catch and ease the joining of the male and female ends of the two shortened rods together.

Further referring now to the invention shown in FIG. 2, it is anticipated that there will be clips or other mechanisms to allow for the placement of the extra or spare shortened rods.

In broad embodiment, the present invention is a device for an application of viscous liquids, or pastes, comprising; a barrel with a cavity for the insertion of a tube of viscous liquids, or pastes, a handle and a trigger with catch and stabilizer for moving a short piston rod and a release for pulling the piston rod back, a plunger with a pan shaped disk removably attached to the center of the plunger wherein the piston rod is a small stabilizer rod that is positioned in a line with the hole in the back of the barrel and the back of the handle.

The advantages of the present invention include, without limitation allowing for the unencumbered use of the caulking gun in restricted space environments. A smaller and more compact caulk gun which allows the caulk to be laid at more precise angles than a larger caulk gun of the prior art would. The use of a set of shortened rods with the plunger assembly permits pressure to be applied to the plunger assembly applying caulk or adhesive without significant clearance behind the caulk gun where the rod would have been.

Since certain changes may be made in the above apparatus without departing from the scope of the invention herein, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative only, and not in a limiting sense.

While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above-described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention. 

1. A caulk gun with a segmented plunger assembly, comprising: a flat round metal plate attached in the center of the plate by a female connection to one or more of a shortened rod with a male connection configured to connect end to end and pass through a hole in the back of the tube housing, a trigger mechanism, a hole in the back of the handle, and a thumb lock mechanism, wherein; the motion of the segmented plunger assembly is regulated by the thumb lock mechanism and the thumb lock groove, the thumb lock groove being located near the back of each shortened rod, the thumb lock mechanism being located on the outside of the hole in the back of the handle; and a handle connected to the shortened tube housing, a thumb lock, and a trigger with a levered connection with a frictional tab.
 2. The caulk gun with a segmented plunger assembly of claim 1, wherein the trigger mechanism comprises a frictional tab attached to a grip which when pulled, pushes the segmented plunger assembly forward into the shortened tube housing.
 3. The caulk gun with a segmented plunger assembly of claim 1, wherein; the segmented plunger assembly is comprised of at least 2 of the shortened rods with a length of less than ⅔ the length of back of the handle to the front of the tube housing and greater than the length of the back of the handle to the back of the tube housing with more of the shortened rods included for attachment to the back end of the segmented plunger assembly.
 4. The caulk gun with a segmented plunger assembly of claim 1, further comprising a clip that attaches to the thumb lock enabling the plunger to be easily pulled out of the tube.
 5. The caulk gun with a segmented plunger assembly of claim 1, wherein; the hole to the tube housing is positioned in a line with the opening at the back of the tube housing, a spring, an opening for a frictional tab, and the hole at the back of the handle.
 6. The caulk gun with a segmented plunger assembly of claim 3, wherein the shortened rods have a male connection and a female connection on opposite sides of the rod, wherein; the male connection and the female connection are comprised of; a short threaded cylinder of complimentary junctions.
 7. The caulk gun of claim 6, wherein the trigger activates a mode in which the segmented plunger assembly is released from the frictional tab to allow for easy movement of the segmented plunger assembly.
 8. A device for the application of viscous liquids, or pastes, comprising; a shortened tube housing with a cavity for the insertion of a tube of a viscous liquid, a segmented plunger assembly which is comprised of; a shortened rod with a threaded gendered connector on one end attached to the center of a round disk, and on the other end of the shortened rod is a threaded connector of opposite gender; and a ring shaped groove that wraps around a substantial portion of the shortened rod near the threaded connector of opposite gender; a handle, comprising: a trigger; a frictional tab disposed around the shortened rod and connected to the trigger such that pulling the trigger collapses the frictional tab onto the shortened rod pulling the shortened rod forward into the tube housing, wherein the shortened rod contiguous with the round disk is a length of less than ⅔ the length of back of the handle to the front of the tube housing and greater than the length of the back of the handle to the back of the tube housing.
 9. The device of claim 8, wherein: more than one of the shortened rods is attached in a contiguous manner to the back of the segmented plunger and the groove is disposed away from the round disk at the front of the segmented plunger.
 10. The device of claim 8, wherein: an opening to the shortened tube housing is turned perpendicular to the axis of the handle.
 11. The device of claim 8, wherein: the shortened tube housing is sized for 9 to 11 ounce tubes or 4 to 7 ounce tubes.
 12. A method for the use of a caulk gun with a segmented plunger assembly, comprising the following steps: identify a place where a standard caulk gun of prior art with a long plunger extending behind the back of the caulk gun would be used at an awkward angle: place the tube of caulk in a shortened tube housing; remove the shortened rods from the segmented plunger assembly such that clearance behind the caulk gun is sufficient to reduce the awkward angle of use; as the tube of caulk is expelled by squeezing the trigger such that the segmented plunger assembly is pushed into the tube housing such that a grove on the back end of the shortened rod is engaged. add more of the shortened rods. 